Find equations in spherical coordinates that describes the following geometric objects in R 3 . Write your equations so that Ļ is a function of Īø and/or Ļ. Hint: find equations for these objects in Cartesian coordinates, and then use the conversion formulas. Simplify your equations as much as possible. (a) The plane z = 2. (b) The sphere of radius 3 centered at (0, 0, 3).